It is dedicated to gathering, researching and preserving artifacts and documents concerning ship transport, international trade, fishing and culture of people working at sea, rivers and those ashore as well as the dissemination of knowledge on maritime history of Poland and its economy through the ages.

[3] In 1977 the museum gained a restored building adjacent to the Crane, and opened a department there named Skład Kolonialny (The Colonial Collection).

[3] Also in 1989, the museum gained the restored granaries on Ołowianka, an island forming the center of the old port in Gdańsk.

In 2012, the Maritime Culture Centre was opened in the building occupied previously by the former Colonial Collection, forming a new branch of the museum.

[3] In 2016 the newest branch, the Shipwreck Conservation Centre (Centrum Konserwacji Wraków Statków), was opened in Tczew, near the Vistula River Museum.